#help-10

1 messages · Page 337 of 1

twilit meteor
#

nice

timid silo
#

yeah

#

pretty smart huh

#

👏

#

asian ?

twilit meteor
timid silo
twilit meteor
timid silo
#

bhai ye dekh ke samaj gaya tha vese bhi

#

😂

twilit meteor
timid silo
#

jee wale hi essa binomial approximation karte hai

#

teachers bhi padhate vese hai :/

twilit meteor
#

true

#

ur 12th or 11th

timid silo
#

any guess ?

twilit meteor
#

12th

timid silo
#

bruh how ?

twilit meteor
#

11th grader wudn't know IBP

#

but u m8 be a guy who already wrote jee last yr

timid silo
#

🤔 which coaching

twilit meteor
timid silo
#

no coaching

twilit meteor
timid silo
#

kota ?

#

last

twilit meteor
timid silo
#

😆 btw 11th me int ?

twilit meteor
twilit meteor
#

not bad. tbh

timid silo
twilit meteor
#

teeachers are pretty good

timid silo
twilit meteor
timid silo
#

it was just bad giving this year again 💀

twilit meteor
#

250 marks gettng just slightly more than 99 percentille

timid silo
#

i messed up

twilit meteor
#

u took drop ah?

timid silo
#

solved integers and ruined

#

its just depressing ugh

#

anyways gonna get 99 atleast this time for sure

twilit meteor
timid silo
twilit meteor
timid silo
#

you done with trigono ?

#

ofc ig

twilit meteor
timid silo
#

posted a problem myself

twilit meteor
#

sure

timid silo
#

close this one

twilit meteor
#

.close

obtuse pebbleBOT
#
Channel closed

Closed by @twilit meteor

Use .reopen if this was a mistake.

obtuse pebbleBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

terse obsidian
#

does anyone know how they got di² in this correlation task?

terse obsidian
#

i dont know how to get di² in this.

#

: (

#

<@&286206848099549185> idk how to describe my problem better if thats what is keeping people from answering. if you need more infos from me i can give them. I basically have the problem that i dont know how they got that di² in the screenshot. the 1, 16 and 0. its from my statistik class

timid silo
#

@terse obsidian egonimo more like ni||gomino||

terse obsidian
#

so i have these tabels for corellation questions. and before i need to get stuff like Pearson's correlation coefficient i need to get di²

timid silo
terse obsidian
#

nevermind i found out. dont need you with your shitty jokes

#

.close

obtuse pebbleBOT
#
Channel closed

Closed by @terse obsidian

Use .reopen if this was a mistake.

obtuse pebbleBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

snow meteor
#

can you help me with some math ? i dont understand and i need it quickly

rotund bolt
#

what is it?

versed stratus
#

need it quickly

#

why

snow meteor
#

where i can show you this ?

versed stratus
#

what's the rush?

snow meteor
#

im doing my homework and i cant do this , i tried like 20 times and it just wrong answer

#

please i really need it

rotund bolt
#

you can send a picture of the question or type it

snow meteor
#

sure

rotund bolt
#

picture preferred

snow meteor
#

i dont understand this

rotund bolt
#

wtf is this

snow meteor
#

i dont know my math teacher did that

versed stratus
#

You're missing a lot of brackets

snow meteor
#

thats the question i asked myself

#

they said its "two fraction digits"

#

or sum

rotund bolt
#

did he just send you this?

snow meteor
#

different shit

snow meteor
#

thats stupid

#

if you answer this for me i will give you bułka

#

are you there ?

rotund bolt
#

solving this without brackets

#

is stupid

snow meteor
#

can you even try that in your way?

#

if its possible?

rotund bolt
#

the 2 consecutive "/" are killing me

snow meteor
#

its like i gues

#

guess*

#

wait

obtuse pebbleBOT
#

@snow meteor Has your question been resolved?

obtuse pebbleBOT
#
Channel closed

Closed due to timeout

Use .reopen if this was a mistake.

obtuse pebbleBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

vast echo
#

struggling with this a lot, i tried getting y and z in terms of x and r and plugging that into the arithmetic series but that gives me a series of 2 equations with 3 unknowns and im not sure if thats possible

vast echo
#

the book gives this hint which seems to suggest using some kind of substitution but i cant see how to make it work

#

<@&286206848099549185>

minor nexus
#

Write your equations

vast echo
#

x + d = 2xr
x + 2d = 3xr^2

#

been playing around with these but i cant figure out how to get r

#

wait i have an idea

#

i might have 0 = 3xr^2 - 4xr - 2x but i dont think that helps either

#

wait i have something

#

nvm that doesnt work

brittle topaz
vast echo
#

oh true

#

i didnt notice that

rotund bolt
#

if x , 2y , 3z is an Arithmetic sequence , 2y-x = 3z-2y

#

=> 4y = x+3z

#

x , y , z is a Geometric sequence

#

y = rx , z = r^2x

#

4rx = x +3r^2 x

#

x gets cancelled out

#

you have a quadratic in r

#

r = 1 , 1/3

brittle topaz
#

dont post solutions

vast echo
rotund bolt
#

hm?

vast echo
#

1 isnt at least

#

since x != y

minor nexus
#

Can you verify?

#

For example if I wanted you to be more fancy, can you tell me for what x you can use? Can you verify your solution(s) for r?

vast echo
#

?

rotund bolt
vast echo
#

i think i got 1/3 with a slightly different answer

#

i got d = 2xr - x, so -x + 4xr = 3xr^2, divide by x and thats the same quadratic

rotund bolt
#

I got the same quadratic

minor nexus
#

None of that is surprising because similar logic should lead to similar conclusions

#

Both of you are using the same basis, AP and GPs

minor nexus
rotund bolt
#

all of that would lead to the same place

#

we're gonna end up with the same quadratic

vast echo
#

.close

obtuse pebbleBOT
#
Channel closed

Closed by @vast echo

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

strange fiber
#

.

obtuse pebbleBOT
strange fiber
#

Can anyone explain to me

#

how is this step crucial?

#

<@&286206848099549185>

errant hemlock
obtuse pebbleBOT
#

@strange fiber Has your question been resolved?

tardy epoch
obtuse pebbleBOT
#

@strange fiber Has your question been resolved?

obtuse pebbleBOT
#
Channel closed

Closed due to timeout

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

regal sequoia
#

Can someone check my proof

obtuse pebbleBOT
regal sequoia
#

Is it accruate

obtuse pebbleBOT
#

@regal sequoia Has your question been resolved?

obtuse pebbleBOT
#

@regal sequoia Has your question been resolved?

low ravine
#

<@&286206848099549185>

hollow glacier
#

EF and DF should be (sqrt(2) x a) and rest of the proof is correct

#

as you calculate ED it is 2a

obtuse pebbleBOT
#

@regal sequoia Has your question been resolved?

regal sequoia
obtuse pebbleBOT
#
Channel closed

Closed by @regal sequoia

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

next magnet
#

hello

obtuse pebbleBOT
next magnet
#

trying to solve this problem

#

turning quadtratic to standard form

#

what do i do with the -3x when i factor?

static furnace
#

probably should've factored it out beforehand no?

next magnet
#

Sorry didnt mean to tag

#

Just natural to “reply” to ppl

static furnace
#

no you're good. you replied to my comment

next magnet
#

But im kinda just following how he did it in examples

next magnet
#

Do u have a vid u’d recommend or maybe if ur able to walk me through?

static furnace
#

are you trying to put it into vertex form?

#

a(x-h)^2+k?

next magnet
#

Yes

static furnace
#

okay so from the very beginning of the problem then I would first start by factoring out the coefficient of x

#

proceeding how you normally would from there will get you where you need to be

next magnet
#

Okay i’ll try

static furnace
#

alright let me know what you get

next magnet
#

Dude i had a pre calc exam on Thursday and i think i failed

#

Might have to drop the course ..

next magnet
static furnace
#

no worries

next magnet
#

ok lemme get cracking at this shit

next magnet
static furnace
#

so factor out 3 from (3x^2+24x)

#

the number in front of the x^2 is its coefficient

#

we dont want a coefficient directly in front of x in standard form

static furnace
next magnet
#

uh

#

okay holdon

static furnace
#

i'll try to find you a video too

next magnet
#

nah i got it now

#

so it would be

#

x^2+8x-16

#

then i do what i was doing before

#

so

#

(8/2)^2 then +16-16 to the equation

static furnace
#

well you currently should have something like -3(x^2+8x+16-16)-48 right?

next magnet
#

and solve

#

i dont have the -3

static furnace
#

oh

next magnet
#

i tht when we divide the 24 and 48 by -3 it cancels it?

static furnace
#

you're not trying to cancel anything, just moving things around

next magnet
#

hm

#

okay

static furnace
#

so factoring it out gives you -3(x^2+8x)-48 right?

next magnet
#

yeah

#

wait

static furnace
#

okay so then you "perfect square" the inside

next magnet
#

how does the 48 stay???

static furnace
#

it's not inside the parentheses

next magnet
#

oh

#

so

#

im only focusing on

#

oh shit

#

wait

#

oops i see now

static furnace
#

lol

next magnet
#

or is it bc u already did the +16-16

static furnace
#

the +16-16 was the next step. the 16 isn't there naturally

next magnet
#

i gotcha

#

okay

static furnace
next magnet
#

so now i just factor 8x - 48?

next magnet
#

shit

#

dude

#

i suck at this wtf

static furnace
#

nah you don't suck at this

#

just takes practice

#

What do you get inside the parentheses? Don't simplify anything yet

next magnet
#

is this chat gonna close

#

i'll try to like text so it stays active

static furnace
#

If it closes, I'll reopen it

#

But I've seen channels open here for a full day as long as you respond to the bot so

#

And if no one responds, including me, feel free to dm me

iron edge
obtuse pebbleBOT
#

@next magnet Has your question been resolved?

next magnet
#

Im active otp !!

next magnet
#

so

#

as it stands

#

i have

#

-3(x^2+8x)-48

next magnet
#

hi @static furnace sorry dont mean to be annoying

obtuse pebbleBOT
#

@next magnet Has your question been resolved?

next magnet
#

no

#

sigh

static furnace
#

yea so -3(x^2+8x) needs to be turned into a perfect square

#

how would you go about doing that

#

@next magnet

next magnet
#

Im not sure, idk what i need to distribute

static furnace
#

you dont need to distribute anything yet

#

just make x^2+8x into a perfect square

#

so (8/2)^2=16 right

#

so -3(x^2+8x+16-16)-48

static furnace
#

following so far?

next magnet
#

Yeah hold on im sorry

next magnet
#

following

#

i got it

#

but idk what im supposed to do with

#

-3(x^2+8x)-48

static furnace
#

what happened to the +16-16?

next magnet
#

well

#

once i solve for whats inside paranthesis doesnt it just cancel out?

static furnace
#

but i put them there to make a perfect square

next magnet
#

okay

#

holdon then

static furnace
#

you see what i'm saying?

next magnet
#

yeah

#

so is

#

+16) - 16 -48

#

right?

static furnace
#

no

#

have to add/subtract them inside the parentheses

next magnet
#

entire thing in ()?

#

ohhhh

#

okay

#

now we are on same page

static furnace
#

okay so -3(x^2+8x+16-16)-48
then -3((x^2+8x+16)-16)-48
and -3((x+4)^2-16)-48

#

is that legible? i can send it through a bot to make it look cleaner

next magnet
#

no thats good

#

hold

#

okay got it

static furnace
#

alright so from here, simplify

#

without expanding the exponenet

next magnet
#

so -16 - 48

static furnace
#

what about -3

next magnet
#

divide?

static furnace
#

from the last equation

#

multiply the -3 to both factors in the parentheses

next magnet
#

uh

#

right

#

wait

#

ohhhh

#

ok ok i see

#

holdon

#

brain is slow rn

#

so it should be

#

-3x+4^2-16+144

static furnace
#

you forgot parentheses somewhere

#

but i dont think thats it

#

should have -3(x+4)^2-3*(-16)-48

next magnet
#

dont i factor -3 ((x+4)^2 - 16) then -3(-48)

static furnace
#

-3*-16?

next magnet
#

i tht that was already in w the x+4

static furnace
#

hmm?

next magnet
#

so now

#

i have

#

-3x+4^2-48-48

static furnace
#

parentheses?

#

where's your perfect square?

#

remember we want it in the form a(x-h)^2+k

next magnet
#

oh wait

#

-3(x+4)^2-48-48

#

meant to do that

#

woops

#

so then

#

i do

#

-48 - 48

#

which would be

#

+48

#

so

#

-3(x+4)^2+48

#

cengage just said im wrong....

#

gonna go fuck myself

static furnace
#

when you multiply the -3 by the -16 what do you get

next magnet
#

48

static furnace
#

right and 48-48 is

next magnet
#

0

static furnace
#

mhmmmm

next magnet
#

oh shit

#

ima kms

static furnace
#

standard form

next magnet
#

right

#

standard form

#

i tht the + k
would cancel out

static furnace
#

hmmm

next magnet
#

chat gpt

#

gave this

static furnace
#

do not use chat gpt

next magnet
#

o

#

uh

#

yeah

#

right

#

lmaooooooo i am trying not to anymore

#

but anywho chat gpt got it wrong too

#

i actually wanna learn man

#

i enjoy math

#

but not this math

#

i like finance related stuff

static furnace
#

i know where we went wrong

#

where I went wrong

next magnet
#

i went wrong when my parents decided to have me

static furnace
#

when I factored out a -3 in the very beginning I forgot a negative

#

should've been -3(x^2-8x)-48

#

not +8x

#

you see what i mean?

next magnet
#

okay one sec

#

yeah

#

im gonna

#

restart

#

from top

#

gimme min

static furnace
#

we originally had (-3x^2+24x)-48

#

taking out a -3 would give us -3(x^2-8x)-48

#

from there we go about the same way we did originally

#

but one of our +'s is now a -

next magnet
#

Look right?

#

-3 (x-4)^2

static furnace
#

as long as that second to last line is +48-48 yes

#

yep!

next magnet
static furnace
#

-3*-16

next magnet
#

right

#

positive

#

okay

#

so wait

#

okay

#

i see

#

bruh i j got logged out of cengage

next magnet
#

we good w that now

#

thank god

#

thank you

#

bro

#

really appreciate it

static furnace
#

yeah no problem!

next magnet
#

so

#

would the axis of symmetry be 4?

static furnace
#

what is the vertex

next magnet
#

or does the vertex become the opposite of x

#

so

#

4,0

static furnace
#

yes

next magnet
#

so

#

axis of symmetry

#

would

#

be 4?

static furnace
#

what is 4

next magnet
#

x = h

static furnace
#

so x=4

next magnet
#

hm

static furnace
#

yes

next magnet
#

why is

#

cengage

#

saying

#

wrong

static furnace
#

y=4

next magnet
#

if x = 4

#

since

#

x = h

#

why

#

is

#

it y

static furnace
#

the vertex is (4,0)

next magnet
#

ohhhhh

#

no

static furnace
#

no?

next magnet
#

cengage still saying wrong

static furnace
#

it says (4,0) is wrong?

next magnet
#

i put

#

y = 4

#

and it said wrong

next magnet
#

i hate cengage

static furnace
#

that's odd

#

standard form is a(x-h)^2+k, where (h,k) is the vertex

next magnet
#

wouldnt it be

#

(0,4)

static furnace
#

would it?

next magnet
#

no clue

#

still wrong

#

i give up man

static furnace
#

im looking at a graph of it right now and it's (4,0)

next magnet
#

why is cengage saying its wrong then wtf

static furnace
#

unsure. but it says that your equation is correct so

next magnet
#

yeah

#

idk

static furnace
#

at least there's that

next magnet
#

thank you again bro

static furnace
#

we're not crazy

#

i promise

next magnet
#

im gonna continue this tmr 🙏

static furnace
#

anytime

#

good luck!

next magnet
#

appreciate the help

#

i was genuinely rlly struggling w this

static furnace
#

hopefully i helped!

#

.close

obtuse pebbleBOT
#
Channel closed

Closed by @static furnace

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

fathom kindle
obtuse pebbleBOT
fathom kindle
#

how do i simplify this

#

the answer is 13√2 but i dont get how

dusk widget
#

are you familiar with the rule that sqrt(ab) = sqrt(a)*sqrt(b)?

fathom kindle
#

yes

dusk widget
#

okay

fathom kindle
#

i just learned it

dusk widget
#

so the issue is this sqrt(32)

fathom kindle
#

ya but its connected to 4

dusk widget
#

what can we factor 32 into?

fathom kindle
#

16 and 2

dusk widget
#

ok

#

then sqrt(32) = sqrt(16)*sqrt(2)

#

what is sqrt(16)?

fathom kindle
#

4

dusk widget
#

right

fathom kindle
#

so its 4√2

dusk widget
#

so 4sqrt(32) - 3sqrt(2) = 4[4sqrt(2)] - 3sqrt(2) = 16sqrt(2) - 3sqrt(2)

#

and you have your answer!

#

does that make sense?

fathom kindle
#

wait so what about the very start

#

the 4 at the begining

#

because instead of 4√32 it changed to 4√2 (which I understand how we got the 4√2)

dusk widget
#

ah so

#

sqrt(32) = 4sqrt(2)

fathom kindle
#

righttt

dusk widget
#

so then 4sqrt(32) = 4[4sqrt(2)]

fathom kindle
#

i see

#

ok thank you!

#

.close

obtuse pebbleBOT
#
Channel closed

Closed by @fathom kindle

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

late zephyr
#

I understand the derivation leading to the memoryless property, but I cant seem to understand its application in a real scenario.

Let say we have a period $P$, in which no event occurs, if the memoryless property is true, it seem to me that the probability that an event occur at any instance $i$ in $P$ is a constant.

The memoryless property is defined as:
$$\mathbb{P}(T> s+t \vert T > s) = \mathbb{P}(T> t)$$
In case of that $t$ is approaching $0$ (i.e the very next instance).
$$\mathbb{P}(T> s+0 \vert T > s) = \mathbb{P}(T> 0)$$

Meaning, the probability that an event occurs in the very next instance equal to the probability that an event occurs the very next moment after initial time. And you can do the same thing for every instance $i$ during $P$.

Meaning, during period $P$ in which no event occurs, the probability of an event occur in any instance $i \in P$ is equal to $\mathbb{P}(0)$.

If that is true, why even has a CDF or PDF, as the value is equal to the CDF at time $0$ anyway.
This has been bugging me several days now, can someone explain it to me ?

warm shaleBOT
vague spindle
late zephyr
#

Sorry i meant the PDF in my last sentence

vague spindle
#

ah

#

well the PDF just retains its value

#

However, over time, as the CDF increases, it eventually hits 1; and by that time the event has to have occurred

#

So it cannot continue past that

late zephyr
#

yeah, but considering period $P$ in which no event occur. The memoryless property seem to suggest that the probability of event occuring at any instance $i$ is the same. Which seem weird to me.

warm shaleBOT
vague spindle
#

It's a bit fallacious to think about the PDF telling us about instantaneous probability

#

The probability of an event happening at an instant is always 0

late zephyr
#

yeah that why i used probability, not PDF

vague spindle
#

But there is no probability of an event occurring at an instant...

#

There is only the probability of an event occurring during an interval

late zephyr
#

okay what if the interval is very very small

vague spindle
#

There's still a probability, just a very very small one (unless of course the PDF is very very large in that interval)

#

Are you familiar with integral calculus?

late zephyr
#

yeah

vague spindle
#

The probability of an event happening during an interval is the integral of the PDF with respect to time over that interval

late zephyr
#

i meant if i chop the periof $P$ into various interval $i$. The memoryless property seem to suggest that the probability of event occuring in all these invertal $i$ is the same

warm shaleBOT
vague spindle
#

That is only true if all the intervals are of the same length

late zephyr
#

Yes

#

that is what i'm saying

#

small and the same length interval

vague spindle
#

Well, you can chop it up into a lot of small intervals...

late zephyr
#

am i missing something here ?blobsweat

vague spindle
#

Possibly...

#

What exactly is confusing you

late zephyr
#

okay

#

ima state my logic again line by line

#

tell me if i get anything wrong

vague spindle
#

alright

late zephyr
#

Memoryless property: waiting does not help, the probability of an event occuring during some interval $s$ does not depend on its past, given that the event hasnt occured in the pass

warm shaleBOT
late zephyr
#

Given a period $P$, chopped into various interval $i$, whose length approching $0$

warm shaleBOT
late zephyr
#

Let $s$ be some time between $0$ and $P$.

warm shaleBOT
late zephyr
#

the memoryless property suggest: $P(T > s + i \vert s) = P(i)$

warm shaleBOT
vague spindle
#

ohhhh i see your confusion here

#

you're thinking of the PDF as unchanging

vague spindle
# warm shale **andy**

However, this has a conditional; it's the probability given that it hasn't happened yet

#

meaning we are constantly updating the PDF to account for the fact that it has not yet occurred; which makes sense as a "memoryless property" if you look at the PDF as scrolling past a fixed playhead (the current time) rather than a playhead moving across the PDF

late zephyr
#

Does that also meant $P(T> s + 2i \vert T > (s+i)) = P(i)$

warm shaleBOT
late zephyr
#

yeah you get what I'm saying right

#

its constant given that an event has not happened

vague spindle
#

yes

late zephyr
#

does that feel weird to you ?

#

its fucking weird man

vague spindle
#

It's a little counterintuitive

#

Probability is pretty wacky tbh

late zephyr
#

yeah, maybe i shouldnt have given it the condition "had not happended"

vague spindle
#

But it can also make sense; think of it as you're constantly stuck at t=0

late zephyr
#

yes

#

that was what i was saying

vague spindle
#

Right now, we can expect events in the future to follow this PDF

#

But in two seconds, we will expect events in the future to follow the PDF shifted over by 2 seconds, assuming nothing happens

#

This is a bit of a Bayesian way of looking at it; that probability is the level to which you expect something to happen

late zephyr
#

okay okay, so you also agree that the is no loop hole in my initial proposition right

#

yeah after the first event happen, it kinda make sense

vague spindle
#

yeah your initial proposition is fairly correct, i think the confusion was how you were looking at PDFs as fixed

#

or at least intuitively expected them to be

#

does it make more sense now?

late zephyr
#

I understand PDF and CDF just fine. It just a bit weird when thinking about the interval before the first event happen.

#

so i brought that cursed intuition to this forsaken land.

#

anyway, thanks man.

vague spindle
#

anytime

vague spindle
obtuse pebbleBOT
#

@late zephyr Has your question been resolved?

#
Channel closed

Closed by @late zephyr

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

chilly scroll
#

a dice thrown three times chance that sum of three numbers appearing is less than 11

chilly scroll
#

so whatim doing

late zephyr
#

how many faces ?

chilly scroll
#

6

#

im

#

Calcing when sum is

#

11 12 13 14 15 16 17 18

late zephyr
#

dont do that

chilly scroll
#

yea

#

im getting a series like

#

10c2 + 11c2 + 12c2 + 13c2

#

idk how to sum these

late zephyr
#

hmmm

#

let start with your approach first

#

what 10c2 ?

chilly scroll
#

okay

#

45

late zephyr
#

no, i meant what does it meant

chilly scroll
#

oh

#

mb

#

I took

#

x+y+z = 11

#

then i gave

#

111

#

So i can use the

#

Bars formula

#

Thingy

#

n+r-1Cr-1

late zephyr
#

you know latex ?

chilly scroll
#

x+y+z=8

#

latex!

#

?

#

idk

#

what's that

late zephyr
#

to write mathematic like this $\mathbb(P)(X)=1/2$

warm shaleBOT
chilly scroll
#

oh this bot

late zephyr
#

did you write down your approch on the paper

chilly scroll
#

yes

late zephyr
#

you can capture it and send it to me

chilly scroll
#

yea hold

#

this is just roughly what im doin

late zephyr
#

why x+y+2 ?

#

you assuming one roll will be 2 ?

chilly scroll
#

nono

#

that's z

late zephyr
#

okay

#

x+y+z = 11 , what does that meant ?

#

you trying to find number of cases where the sum of the rolls is 11 ?

chilly scroll
#

oh wait

#

Yeaaah

#

Damn

#

It just hit

#

rip

late zephyr
#

you need any help with the rest ?

#

its just counting

chilly scroll
#

ye this is plain wrong

#

how do i do

late zephyr
#

okay

#

let answeer this first

#

ill write down 3 number, which is 3 of my rolls

#

so the first roll i got is 443

#

the second roll i got is 344

#

does they count as the same roll ?

chilly scroll
#

same thing

late zephyr
#

okay

#

you familiar with Set ?

chilly scroll
#

yes

late zephyr
#

okay what is the set of possible value ?

chilly scroll
#

6^3

late zephyr
#

you sure ?

chilly scroll
#

is it not

late zephyr
#

i dont know haha

chilly scroll
late zephyr
#

okay let count the case in which the sum is 3

chilly scroll
#

216 is right ithink

late zephyr
#

only 1 case right {1,1,1}

chilly scroll
#

yes

late zephyr
#

how many if the sum is 4 ?

chilly scroll
#

oh damn

#

3?

late zephyr
#

does {1,1,2} and {2,1,1} different ?

chilly scroll
#

aah

late zephyr
#

if they are the same then there only 1 case

chilly scroll
#

I think if you see it

#

Pnc way the order does matter

#

but the qn just meeds the sum to be 11

#

So ig that way it counts 1

late zephyr
#

i dont know your problem, i just trying to set you on the right track

#

now

chilly scroll
#

o

late zephyr
#

Let assume

#

the first roll is 1

chilly scroll
#

ye

late zephyr
#

so for the two rolls: there sum will be from 2->10 right ?

chilly scroll
#

Can be 12 11 too?

late zephyr
#

no

#

becasue it have to be less than 11 total

chilly scroll
#

oh ye

#

okay

late zephyr
#

okay for 2 dices, can you calculate the probability of its sum equal 2 ?

chilly scroll
#

1/36

late zephyr
#

it sum equal 3

chilly scroll
#

or wait

#

1/18

late zephyr
#

and from these, can you count the number of occurences, in which the first roll is 1, sum with the other two less than 11 ?

chilly scroll
#

Imma try

late zephyr
#

okay

#

there is a pattern

#

just take it very slow

#

write it down

#

you'll see

chilly scroll
#

@late zephyr also is there a formula for that series

late zephyr
#

im not aware of that, im just counting cases here

chilly scroll
#

Sigma Rc2

#

I come across a lot

#

oh

late zephyr
#

my hints is, count the number of cases so that two dices sum up to a certain number, then for each value of the third dice. Sum it with the acceptable number of cases in the two dices.

#

remember to multiply by 3, as the third dice can be anywhere in the sequence

#

if you want to use undergraduate formula, look up multinomial distribution

But I want to help you build an intuition before using formula.

chilly scroll
#

damn thanks ye

#

@late zephyr i found no of cases

#

For 2 rolls

#

sum

#

From 2 to 10

late zephyr
#

okay, so let assume that the third roll is 1

#

how many case we got for it ?

chilly scroll
#

19

#

But

late zephyr
#

sum = 2, sum =3, ..., sum =10 right ?

chilly scroll
#

yes

#

For 2s

#

Do we permute them too

#

Cuz if yes

#

Then its just messy

late zephyr
#

try it

chilly scroll
#

if there's a repition

#

i would have to

late zephyr
#

yup there are formula to delete these repititions

#

for example in case of sum of two dice

#

equal 2 we got 1 case right ?

#

equal 12 we got how many ?

chilly scroll
#

1 ye

late zephyr
#

equal 3 and equal 11 ?

chilly scroll
#

22

#

2,

late zephyr
#

equal 4 and equal 10

#

its like it symmetric right ?

chilly scroll
#

3

#

oh yea

late zephyr
#

this is what called a normal distribution

chilly scroll
#

ahh

late zephyr
#

watch this later

#

now let go back to our problem

chilly scroll
#

okok

late zephyr
#

which sum have the most cases (two dice)

chilly scroll
#

7

#

6 cases

late zephyr
#

is it symmetric with the center at 7 ?

chilly scroll
#

ye ig

#

2+12/2

late zephyr
#

-1

#

anyway

chilly scroll
late zephyr
#

continue

chilly scroll
#

is it not?

late zephyr
#

its 2+12/2 -1

chilly scroll
#

Oh i meant

#

(2+12)/2

late zephyr
#

okay

chilly scroll
#

yeye

late zephyr
#

let step back form our problem a bit

#

how many number are between the interval 1-10 contain

#

only integer

#

10 number right ?

chilly scroll
#

Ye

late zephyr
#

but 10 -1 equal 9 ?

#

you gotta plus 1

chilly scroll
#

Ye

late zephyr
#

you see your hand

#

let number the your finger 1 to 5

#

how many gap do you got ?

chilly scroll
#

yes i know that rule for counting we subtract the extreme and add 1 rigg

late zephyr
#

the interval and the actual 'mark' is a bit different

chilly scroll
#

Oh

late zephyr
#

on your hand, there is 5 number

chilly scroll
#

yes

late zephyr
#

but 4 interval right ?

chilly scroll
#

interval?

late zephyr
#

the gap between your finger

chilly scroll
#

Oh yes

#

yes

#

ah so thats

late zephyr
#

this

#

that why you +1 and -1 in some calculation

chilly scroll
#

Icic

late zephyr
#

you can ponder that later

#

let get back to our problem

chilly scroll
#

okay

late zephyr
#

if the thrid roll is 1

#

you sum up the cases for 2-10 right

#

thrid roll is 2

#

you sum up for 2-9

chilly scroll
#

Yesyes

#

ic

late zephyr
#

oh less than 11

#

mb

#

thrid rolls 1
you sum up for the cases 2-9

chilly scroll
#

ok

late zephyr
#

thrid rolls 2
you sum up for the cases 2-8

#

do the same thing for all third roll

#

and sum them all up

chilly scroll
#

ok wait

obtuse pebbleBOT
#

@chilly scroll Has your question been resolved?

obtuse pebbleBOT
#
Channel closed

Closed due to timeout

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

blissful bane
#

is the reason rolle’s theorem requires continuity on closed interval [a,b] is to have extremum value property of continuous functions on compact sets?

blissful bane
#

like we can always guarantee existence of maximum/minimum with in the set unlike (a,b)

#

<@&286206848099549185>

fathom flicker
obtuse pebbleBOT
#

@blissful bane Has your question been resolved?

blissful bane
#

@fathom flicker yes my proof uses extremum value theorem of compact sets and interior extremum value

fathom flicker
#

Examine what would go wrong in the proof if there was not guaranteed an extreme value

obtuse pebbleBOT
#
Channel closed

Closed due to timeout

Use .reopen if this was a mistake.

obtuse pebbleBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

summer sentinel
obtuse pebbleBOT
summer sentinel
#

!status

obtuse pebbleBOT
#
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
summer sentinel
#

3

#

my answer is 0.1

#

their given answer is 10.09

ember frost
#

how did you arrive to your answer?

summer sentinel
#

I find the original blood value

#

then the new blood value

ember frost
#

what was the original blood value?

summer sentinel
#

60/11

ember frost
#

what was the new blood value?

summer sentinel
#

6

ember frost
#

so how did you find the percent change?

summer sentinel
#

i used the formula

#

(new-old)/old

#

<=> (3-60/11)/60/11

#

=0.1

ember frost
#

hm, it is 0.1 indeed

#

but the question asks for the percent

#

not the ratio

#

so what do you do?

summer sentinel
#

times 100?

ember frost
#

yes

#

so it would be 10%\

ember frost
#

but rather its rounded-to-two-decimal-places value: 5.45

#

hence, 10.09%

summer sentinel
#

OHH

#

wow

#

i DID NOT expect that

ember frost
#

the more you know

#

since the problem asks the value be rounded to two decimal places, i suggest you obey it and dont use 60/11

summer sentinel
#

thanks for your help

#

.close

obtuse pebbleBOT
#
Channel closed

Closed by @summer sentinel

Use .reopen if this was a mistake.

obtuse pebbleBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

fathom flicker
obtuse pebbleBOT
fathom flicker
#

I have a question about my proof for this because it feels wrong but I can't find any issues

#

Let v1, ... vn be a basis of V since it is finite-dimensional, and let 1 be a basis of F.

#

Then I have a theorem that says there exists a unique linear map phi:V->F such that
phi(v_i)=w_i

#

and in this case since there is only one w_i and it is 1, we have a unique linear map phi:V-<F such that
phi(v_1)=1

#

So, my proof states that since v is non-zero, we can use it as the first basis vector of V, so letting v_1=v, and we can extend this to a basis

#

so we have phi(v)=1

#

Does that work?

dense imp
#

can I ask some questions about this since I haven't taken LA since the age of dinosaurs? :p

fathom flicker
#

Sure

dense imp
#

what is V' ? and also what is F in the proof?

fathom flicker
#

V' is the set of linear maps from V to F

#

and F is the field V is defined over

dense imp
#

hm what is meant by a basis of a field?

#

is that a thing?

fathom flicker
#

every field is a vector space

#

and in our class F is either C or R, so 1-dimensional

dense imp
#

ok gotcha i think

#

yeah your argument make sense to me

fathom flicker
#

I feel like it can't be right

#

I must be missing something

#

Yes I am

dense imp
#

it doesn't seem that surprising that there would be such a function

fathom flicker
#

so it breaks there

fathom flicker
#

and it is so

#

any better ideas?

dense imp
#

isn't V' a vector space too

wild swallow
#

i mean its not unique right

#

like if you set phi(v_1) = 1, you could also set phi(v_2) = whatever

fathom flicker
#

Yeah my proof does not work

wild swallow
#

well it actually does

fathom flicker
wild swallow
#

but you just stated some details which arent quite right

fathom flicker
#

the theorem I used is false here

haughty coyote
# fathom flicker

My idea:
||Complete v into a basis then let phi be the projection on the first coordinate||

polar fossil
wild swallow
#

the uniqueness is false

fathom flicker
timid silo
#

@fathom flicker

#

The answer is literally simple

#

Think harder

#

Lol

#

It way easier than you think

wild swallow
#

Blud...

timid silo
#

I figured it out in less than 1 minutes

haughty coyote
timid silo
#

In my head

haughty coyote
timid silo
#

Hopefully it helps

fathom flicker
#

Okay thanks

#

now fuck off

dense imp
#

if you have any linear map T that has some vector v1 that isn't in the nullspace then T(v1) = f where f is nonzero right, then wouldn't the linear map 1/f T(v1) = 1

timid silo
#

ok

wild swallow
haughty coyote
#

For anyone familiar with linalg, the answer should be "yeah it's obvious" in 5 seconds so you can process the question

#

Let's end this

polar fossil
#

hmmCat that theorem only guarantees uniqueness if they have the same dimensions but if one is lower dimension than the other it should still work right?

timid silo
#

@fathom flicker i'm assuming you're a beginner since you posted a very basic question. i didnt mean to come off as rude, sorry

zenith raft
#

who is this clown

fathom flicker
timid silo
#

??

#

how am i trolling

#

please elaborate

haughty coyote
zenith raft
#

i doubt he knows any linear algebra either

polar fossil
timid silo
timid silo
dense imp
#

@fathom flicker also if you wanna use that theorem you mentioned, could you consider the span(v1) as a 1 dim subspace of V and consider then the linear transformation that the theorem guarantees from span(v1) -> F then extend it into a LA defined on all of V

haughty coyote
timid silo
#

please read the context before using any of my messages against me

polar fossil
#

you can pick where each basis vector ends up, right?

#

like independently of each other

dense imp
#

i think so?

wild swallow
#

this has a fancy name called the "universal property of vector spaces"

zenith raft
polar fossil
#

it actually changed two words

fathom flicker
#

Okay

#

so albeit with some inspiration from everyone

#

I have a new proof

#

Which hopefully works

zenith raft
#

i hope

fathom flicker
#

definitely not

#

Since v is in V and v !=0 span(V) is a 1D subspace of V with basis v. We can let 1 be a basis of F. Then by previously mentioned theorem there exists a unique linear map phi:span(v)->F such that phi(v)=1. Now we can extend v into a basis of V using w1, ... wn. Then we can extend phi to map all w_i ->0 and we have that phi:V->F has phi(v)=1.

#

This seems better, does it work?

wild swallow
#

idk why you want to use uniqueness

#

the question doesnt say that phi needs to be unique

fathom flicker
#

Well I don't need it

#

but it's included in the theorem statement

wild swallow
#

you can just map v to 1

#

you dont need that theorem

fathom flicker
#

okay but using this theorem I dont have to justify thats a linear map

wild swallow
#

that theorem is specifically for vector spaces of the same dimension

fathom flicker
#

span(v) and F have the same dimension

wild swallow
#

you should know that for vector spaces, specifying where the basis maps to defines a unique linear map

polar fossil
wild swallow
#

yeah lol

#

thats pretty much all you have to say

fathom flicker
#

how is that a proof then

#

let phi(v)=1

#

done

polar fossil
#

so you clearly can't assume it...

haughty coyote
wild swallow
#

you choose a basis of V containing v

#

then map v to 1

#

thats literally it

fathom flicker
#

why can u map v to 1

wild swallow
#

because its part of the basis

polar fossil
fathom flicker
#

why can u map any part of the basis to 1

haughty coyote
wild swallow
#

because thats what vector spaces are

#

a map of vector spaces is uniquely determined by what happens on the basis

fathom flicker
#

so my answer should be "this is what vector spaces are, let phi(v)=1 q.e.d"

wild swallow
#

thats why matrices work

dense imp
#

@fathom flicker what about this:

extend v to a basis for V: {v, v2, v3...v_n}
for some vector w in V let {c1, c2,...c_n} be the unique coefficients of the linear combination of w in terms of the basis: i.e. w = c1(v)+c2(v2)+...c_n(v_n)
define phi(w) be the function where phi(w) = c1
you can verify this is a linear transformation V -> F so it is in V' and it fulfills the property phi(v) = 1

wild swallow
#

it pretty much should be

fathom flicker
#

so we're all having fun proving this

#

except Snow

dense imp
#

😄

wild swallow
#

this is all just spelling out the fact that a linear map is determined by its values on a basis

dense imp
#

isnt linear algebra all about expressing the same thing in like a zillion ways

fathom flicker
#

No it is about y=mx+b

haughty coyote
haughty coyote
wild swallow
#

note that phi doesnt need to be 0 elsewhere

fathom flicker
#

okay thank you everyon

#

especially yungtrapps and layla